Primary Capacitors

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raiderUM

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We have a primary capacitor that has been off for a very long time. No body know why its off, but I think it might off because the switches we have are not rated for capacitor loads?? We have a loop system where I work that feeds many buildings and we are able to isolate buildings and make sure everyone has power in case of an outage.

The location we have the Capacitors off is one of our many 4160V distribution centers. There is 450KVAR total at this location with a vacuum switch.

What kind of information do I need to be looking for to find out if this CAP Bank can be compatible with the Primary switches that we have all across our complex that feeds our loop system?? I believe this is the reason the CAP bank is not in operation. It was installed in 1990 and we have electricians who have been here almost 30years who do not know why it has been turned off. There has never been a fault of any kind the unit is just turned off.

Thank you
 
Capacitors have been known to cause at least as many problems as they solve. I would not turn this unit on without a thorough investigation as to its affect on your power grid.
 
jim dungar said:
Capacitors have been known to cause at least as many problems as they solve. I would not turn this unit on without a thorough investigation as to its affect on your power grid.
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Very true. I am trying to get as much information before we call in a consulting engineering group
 
Do you know your current power factor? Depending on your system, they could be too big.
 
Hv&Lv said:
Do you know your current power factor? Depending on your system, they could be too big.
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Yes I know my current PF. It averaged .8932 last year and we consumed 169,700 KW on average and KVA was 190,000. Meaning we could have saved (190000-171414)=18586Kva. Kva is what we are charged for, which relates directly to PF. Which is and avg of 7200 per month. So I would say the system could handle it
 
raiderUM said:
Yes I know my current PF. It averaged .8932 last year and we consumed 169,700 KW on average and KVA was 190,000. Meaning we could have saved (190000-171414)=18586Kva. Kva is what we are charged for, which relates directly to PF. Which is and avg of 7200 per month. So I would say the system could handle it
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Where are you that they charge for kVA and not kW? I want to know so I do not move there...
 
Jraef said:
Where are you that they charge for kVA and not kW? I want to know so I do not move there...
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Haha, we do get charged for KW. We also get charged a KVA demand charge which is a lot of money when you consider the numbers in my previous post. We are always going to be charge for KVA but by improving PF it can lower that amount that we have to pay for KVA
 
raiderUM said:
Haha, we do get charged for KW. We also get charged a KVA demand charge which is a lot of money when you consider the numbers in my previous post. We are always going to be charge for KVA but by improving PF it can lower that amount that we have to pay for KVA
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The demand charge you are speaking of is kW demand, or power. Along with that is the energy charge...
You don't get charged for kVa, if you do, I agree with Jraef..
 
Hv&Lv said:
The demand charge you are speaking of is kW demand, or power. Along with that is the energy charge...
You don't get charged for kVa, if you do, I agree with Jraef..[/QUOTE

We pay a Demand Charge which is in KVA at almost $10 per and an Energy Charge which is in KWH.
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raiderUM said:
Hv&Lv said:
The demand charge you are speaking of is kW demand, or power. Along with that is the energy charge...
You don't get charged for kVa, if you do, I agree with Jraef..[/QUOTE

We pay a Demand Charge which is in KVA at almost $10 per and an Energy Charge which is in KWH.
Click to expand...

You may want to double check what that charge is actually for to make sure you understand it.

To start with KVA is power and KWH is energy. The base of your billing is energy, additional penalties come from low power factor or peak demands.
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kwired said:
You may want to double check what that charge is actually for to make sure you understand it.

To start with KVA is power and KWH is energy. The base of your billing is energy, additional penalties come from low power factor or peak demands.
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Most 'industrial' power bill contain two components: one based on KWHR and the other on KVA demand.

The OP would need to know the PF at the 'highest' kVA demand charge point in order to factor in the cost benefit of capacitors.
for example, lightly loaded induction motors have poor power factor, but they also have low kVA demand.
 
kwired said:
raiderUM said:
You may want to double check what that charge is actually for to make sure you understand it.

To start with KVA is power and KWH is energy. The base of your billing is energy, additional penalties come from low power factor or peak demands.
Click to expand...

KVA demand charge is Peak KW. We do not have PF penalties but (KW/KVA = PF) so by getting my PF closer to unity "1" the less KVA demand charge I have to pay.
Click to expand...
 
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